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Stan Smith
11-17-2014, 2:14 PM
I'm turning an large goblet from ambrosia maple. I drilled a 1/4" hole part way into the end grain and have begun hollowing. I didn't get very far and didn't like how my carbide tool was working. This maple is pretty hard and I thought a gouge would be better. I tried a small spindle gouge, regular grind, and it worked better. I decided to get a 3/8 bowl gouge from Thompson. I have not done any shaping on the outside.

I'm sort of confused about which way to proceed. I've read some stuff that says to form the outside first and seen some youtubes and do the inside first. I read some that say to turn from the center out and other stuff that say to turn from the rim to toward the center. I don't have any gouges with a fingernail profile except my Thompson detail gouge. I've used my berger tool for most of the limited amount of hollowing work that I've done in the past and this goblet is much larger, 4.5" diameter. I just got a 3/8 bowl gouge from Thompson that I would like to use, but am not sure if I go from the center or vice versa. Thanks for any suggestions.

Bruce Pratt
11-17-2014, 3:05 PM
Maybe unconventional, but this is my method.

1. Round stock between centers.
2. Put a tenon on the foot end of the cylinder and mount in 4 jaw chuck
3. Drill from tail stock ~3/4 of intended depth of goblet bowl will drill bit of choice (optional)
4. Remount tailstock with 60 degree cone in drill hole
5. Shape the outside of the bowl of the goblet, to about 2/3 the way down from the rim
6. Mount a bowl steady on the front side of the lathe, about 1/2 way down the bowl (could also use full spindle steady at this point).
7. Hollow out the entire bowl of the goblet, with a combination of Hunter carbides and half round scrapers, with cuts from center to edge. If you have a 360 degree capture spindle steady you can do your cuts in either direction.
8. Move the bowl steady to the back side of the lathe
9. Finish the outside profile of the bottom 1/3 of the bowl.
10. Shape the foot and stem (w/ or w/out captured rings). If the geometry works, push a 60 degree cone live center into the bottom of the bowl of the goblet for extra stability when doing the foot and stem.
11. Plan for the bottom of the foot to be 3/8-1/2" away from the chuck jaws so you can part off the goblet with a thin parting tool.

Scott Hackler
11-17-2014, 3:08 PM
Stan,

Almost everyone I've ever seen make a hollowed out ....anything... the outside profile is always done first. The inside, while we try our hardest, is secondary to the exterior. Mostly because that is the most visible portion. Having said that, you must NOT turn a goblet (or hollow form or vase) to its complete final shape past the "bowl" portion, because you need support for the wood hanging away from the headstock. Shape the cup, done to the stem area and leave at least an 1" to 2" for support until your done hollowing out the cup.

Drilling a hole to the desired depth is a great technique and that is what I teach in my demos. If you are turning end grain orientation, cut from the center to the rim and the opposite for side grain (although you shouldn't punish yourself by trying to turn a goblet in side grain orientation!) That way you are doing pull cuts into SIDE GRAIN, and the end grain monster wont bother you too much.

Take it down to 1/2" or so and if you want it thinner, work it down in 1/2 to 1" sections starting at the rim. Do not return to the thin sections as you progress towards the bottom.

The Thompson tools are a favorite of mine and I like to extend the wings way back just to allow a better "blending zone" on the tool when I do very light scraping cuts to blend the areas I have thinned down.

Good luck, be safe.

Mike Golka
11-17-2014, 4:55 PM
Stan you've received some great advice so far, the only thing I will add is that I prefer the "Termite" ring tool for end grain goblets. It dose a good job of shear cutting the grain and makes it easy to make a nice curve at the bottom. It does take a little time to get onto. You start with the hole in the ring running horizontal so that the ring edge makes contact in the same way a tire contacts the road if that makes any sense. You then rotate the ring slightly clockwise to take more wood off.

Thom Sturgill
11-17-2014, 5:43 PM
To understand the issue of cutting endgrain hold one hand with the fingers toward your body. the fingers represent the fiber cells of the timber. Now think of the palm as the base of the bowl. If you hollow from the base outward on the inside each fiber is supported by the one outside of it. On the outside it is the opposite.

I usually use a 3/8" bowl gouge to rough - cutting inward with light cuts and very sharp gouge. Then finish with a bowl scraper from center outward in shear scrape mode. Most of my goblets are smaller at the opening than at the widest part. Outside is cut about 3/4 of the way. I tried hollowing then shaping the outside ONCE. With practice it may be a better way, but the learning curve would be steep for me.

Steve Paxman
11-17-2014, 6:14 PM
I usually use a carbide tool for end-grain hollowing, but it's one of those with a slight cup to the profile - not just the round flat one. Works great, cutting from the inside center towards the rim.

Stan Smith
11-17-2014, 10:30 PM
I usually use a carbide tool for end-grain hollowing, but it's one of those with a slight cup to the profile - not just the round flat one. Works great, cutting from the inside center towards the rim.

Hi Steve. Just wondering if the tool you use is like this one which I have. Mine is a Harrison smoother-hollower tool. So far I have not used it much as I have another Harrison hollower without the cup profile. If mine is similar to yours, I'll give it a try. I'm also going to try my new bowl gouge.

300456

I'm mulling over the other good suggestions also.

Stan Smith
11-17-2014, 10:43 PM
Just thought I should post a pic of an example that I'm going to use as a very general idea. The over all length will be approximately 10". The cup will be about 1/2 and the stem and base the other half. I'm intentionally making this beefy since it will be used for communion. Again thanks to all for your valued comments.

300457

Steve Paxman
11-18-2014, 12:30 AM
Hi Steve. Just wondering if the tool you use is like this one which I have. Mine is a Harrison smoother-hollower tool. So far I have not used it much as I have another Harrison hollower without the cup profile. If mine is similar to yours, I'll give it a try. I'm also going to try my new bowl gouge.

300456

I'm mulling over the other good suggestions also.

Stan, that's exactly the tool I have. I love the harrison specialties tools.

I show my technique for hollowing with that exact tool in this video: http://youtu.be/cmaUUSUQw4E

That's part 2 of my three-part "Can I do it with carbide" series on my youtube channel. My whole channel is pretty much about woodturning with carbide tools. I have regular HSS tolls too, I just don't usually use them much in my videos, except for the skew. Can't live without a skew. :)

Let me know if you have any more questions about it, and good luck!
- Steve

Bruce Pratt
11-18-2014, 8:55 AM
Hunter carbides also have the same profile and round shaft.

Bruce Lewane
11-18-2014, 1:39 PM
I've been giving One way's Termite a test drive.
The carbides are good for rough hollowing while
the Termite makes great finish cuts.

Stan Smith
11-18-2014, 3:22 PM
@Steve...Great job on the video. I have the Harrison diamond tool, but I use the EW easy start detailer a lot more. I like the carbide tools, but I also like my gouges and also the skews. I'm going to watch the other 2 parts to your vid's which I really appreciate. Thanks.